In the past, a drum washing machine enables a drum of horizontal axis type to rotate in an outer tank the bottom of which is stored with water, washings are lifted up and dropped down by baffles arranged in the drum, and the washings are thrown to an inner circumferential surface of the drum to realize washing.
In this way, in a structure of stirring the washings by the baffles, the washings are difficult to twine or rub against each other. Therefore, compared with an automatic washing machine in which the washings are washed by rotating a pulsator in a washing and spinning tank, a mechanical force acted on the washings by the drum washing machine tends to be smaller, and the detergency tends to be degraded.
Therefore, as for a drum washing machine, a following structure may be adopted so as to improve the detergency, in the structure, a rotating body having a protruding part on the surface thereof is arranged at an end part of the drum, and the drum and the rotating body are enabled to rotate at different rotation speeds during washing and rinsing. During spinning by the drum washing machine, the drum and the rotating body rotate in a manner of spinning the washings properly, i.e., rotate at a same rotating speed.
For example, a driving part for rotating the drum and the rotating body may adopt the following structure: the driving part is provided with a driving motor for the drum and a driving motor for the rotating body, the rotation of the driving motor for the drum is transferred to a rotating shaft of the drum by transmission belts and pulleys so as to enable the drum to rotate, and the rotation of the driving motor for the rotating body is transferred to a rotating shaft of the rotating body by transmission belts and pulleys so as to enable the rotating body to rotate (with reference to a patent literature 1).